#define _CRT_SECURE_NO_WARNINGS
char** letterCombinations(char* digits, int* returnSize)
{
    *returnSize = 0;
    int len = strlen(digits);
    int i = 0;
    int j = 0;
    int n = 0;
    int count = 0;
    for (i = 0; i < len; i++)
    {
        if (digits[i] == '7' || digits[i] == '9')
        {
            (*returnSize) += 4;
        }
        else
        {
            (*returnSize) += 3;
        }
    }
    char** ret = (char**)calloc(*returnSize, sizeof(char*));
    char* arr = (char*)calloc((*returnSize) * (len + 1), sizeof(char));
    for (i = 0; i < len; i++)
    {
        if (digits[i] == '7' || digits[i] == '9')
        {
            for (j = 0; j < 4; j++)
            {
                for (n = 0; n < )

            }
        }

    }
}